CN1430702A - Driving controlling apparatus for reciprocating compressor - Google Patents

Abstract

A driving controlling apparatus for reciprocating compressor using resonance, uses resonance increased in the current corresponding characteristic by compensating the inductance value of a coil turned inner part of the motor using a capacitor. A electric circuit further comprises a capacitor for compensating the inductance of the coil which is wound around the motor of the reciprocating compressing unit, accordingly, the burden of the applied voltage against the inductance is reduced, so low applied voltage can generate the stroke needed and the variation of the current hardly effect to the variation of the stroke. Therefore, stable load characteristic is maintained because the stroke variation is low even if the load variation is generated.

Description

The driving-controlling device that is used for reciprocal compressor

Technical field

The present invention relates to a kind of driving-controlling device that utilizes the reciprocal compressor of resonance, be specifically related to a kind of so a kind of driving-controlling device that utilizes the reciprocal compressor of resonance, promptly it has high electric current resistance characteristic by the inductance value of using a capacitor to offset the coil in motor.

Background technique

Generally, in reciprocal compressor, utilize the power supply that switch gear cuts out to be provided to the coil at multi phase stator, so that therefore rotate moment.In this respect, by changing the excited state between rotor and stator in regular turn, can produce forward rotation moment by the magnetic power taking.

If concrete excited state does not change, then rotor can stop at certain position, and by a maximum induction is put the phase place of controlling the input pulse signal that is applied to switch gear to start with, can produce counterrotating power.

Utilize so various drive controlling that can obtain, reciprocal compressor is suitable for requiring directly to control the electronic product of motor.

Especially,, can change compressibility, therefore, can change refrigeration power (cooling force) according to user's wish by the voltage that is applied to motor for the reciprocal compressor that is used for refrigerator or air-conditioning.

Describe reciprocable machine in detail below with reference to Fig. 1.

Fig. 1 is the skeleton diagram of structure that the driving-controlling device of general reciprocal compressor is shown.

As shown in Figure 1, general reciprocal compressor comprises: reciprocating type compression unit (L.COMP) is used for changing the stroke of piston motion by the voltage that is applied to motor internal with control refrigeration power according to stroke command; Voltage detector 30 when being used to work as the voltage raising stroke that is applied, detects the voltage that produces at reciprocating type compression unit (L.COMP); Current probe 20 when being used to work as the voltage raising stroke that is applied, detects the electric current that is applied to reciprocating type compression unit (L.COMP); Microcomputer 40 is used to utilize the voltage and current that is detected by voltage detector 30 and current probe 20 to calculate stroke, relatively stroke and stroke command and the corresponding switch controlling signal of output; Circuit unit 10 is used for closing AC power supplies according to the switch controlling signal of microcomputer 40 with TRIAC, to apply voltage to reciprocating type compression unit (L.COMP).

The following describes the operation of conventional reciprocating formula motor with described structure.

At first, in reciprocating type compression unit (L.COMP), piston moves by the voltage that applies according to the stroke command that is provided with by the user, therefore, changes stroke and controls refrigeration power.

Simultaneously, when the connection cycle of the TRIAC (Tr1) of circuit unit 10 is prolonged by the switch controlling signal of microcomputer 40, improved the stroke of reciprocating type compression unit (L.COMP).At this moment, the voltage and current that is applied to the motor (M) of reciprocating type compression unit (L.COMP) is detected by voltage detector 30 and current probe 20, and is applied to microcomputer 40.

Then, microcomputer 40 utilizes the electric current and the voltage that are detected by current probe 20 and voltage detector 30 to calculate stroke.

Described stroke is compared with stroke command, to export corresponding switch controlling signal.

That is, if the stroke that is calculated less than stroke command, then microcomputer 40 output one switch controlling signal prolongs the on time of TRIAC (Tr1), so that improve the voltage that is applied to reciprocating type compression unit (L.COMP).

But, if the stroke that is calculated greater than stroke command, microcomputer 40 output switch control signals then are used to shorten on time of TRIAC (Tr1), to reduce to be applied to the voltage of reciprocating type compression unit (L.COMP).

The voltage and the relation between the stroke that are applied to motor (M) can be represented with following equation (1) $V=L\frac{\mathrm{di}}{\mathrm{dt}}+R\·i+\mathrm{\α}\·\stackrel{\→}{S}---\left(1\right)$ Wherein α represents constant of the machine, and being used for power conversions is mechanical force, The expression stroke.' R ' is the internal resistance of motor, the inductance of ' L ' expression motor (M) itself.

Inductive drop ( ) almost with counterelectromotive force (

) identical, with counterelectromotive force (

Compare, the voltage of internal resistance (R) can be ignored.

Therefore, the voltage (V) that is applied to motor (M) by inductive drop (

) and counterelectromotive force (

And determine, in order to produce needed stroke, should improve the voltage (V) that is applied to motor.

At this moment, in order to improve the efficient of reciprocal compressor, should be little in inductance (L) value of the coil of motor (M) itself, the inductance of coil (L) value diminishes when the size increase of motor (magnet).

Therefore,,, then increased air gap, caused problem: the whole size and the cost that have improved reciprocal compressor if increase the size (thickness of magnet) of motor in order to improve the efficient of reciprocable machine.

Simultaneously, if reduce the size (thickness of magnet) of motor, then inductance (L) value at the coil of motor (M) is increased.Then, will work lentamente according to the electric current of the magnitude of voltage of the stroke of reciprocal compressor control, so stroke is not controlled smoothly.

Technological points of the present invention

Therefore an object of the present invention is to provide the driving-controlling device of reciprocal compressor, it makes the slack-off character of current practice characteristic have fabulous electric current by counteracting and resists ability when the inductance value of the coil in motor is enhanced by the use capacitor.

Summary of the invention

In order to realize described purpose, a kind of driving-controlling device of reciprocal compressor is provided, it has: a reciprocating type compression unit is used for changing the stroke of piston motion by the voltage that is applied to motor internal with control refrigeration power according to stroke command; A circuit unit is used to utilize TRIAC switch AC power supplies and it is applied to the motor of reciprocating type compression unit, and wherein circuit unit comprises a capacitor, is used to offset the inductance of coil of the motor of reciprocating type compression unit itself.

Description of drawings

Fig. 1 is the skeleton diagram of structure of the driving-controlling device of traditional reciprocal compressor;

Fig. 2 is the figure that illustrates according to the structure of the driving-controlling device of the reciprocal compressor that utilizes resonance of the present invention.

Embodiment

Below, describe the operation and the effect of the driving-controlling device of reciprocal compressor in detail with reference to accompanying drawing.

Fig. 2 is the figure that illustrates according to the structure of the driving-controlling device of the reciprocal compressor that utilizes resonance of the present invention.

As shown in Figure 2, the driving-controlling device of reciprocal compressor comprises: reciprocating type compression unit (L.COMP) is used for changing the stroke of piston motion by the voltage that is applied to motor internal with control refrigeration power according to stroke command; Voltage detector 30 is used for detecting the voltage that produces at reciprocating type compression unit (L.COMP) when the voltage that passes through to be applied improves stroke; Current probe 20; When being used to work as the voltage raising stroke that is applied, detect the electric current that is applied to reciprocating type compression unit (L.COMP); Microcomputer 40 is used to utilize the voltage and current that is detected by voltage detector 30 and current probe 20 to calculate stroke, relatively stroke and stroke command and the corresponding switch controlling signal of output; Circuit unit 10, has an electric capacity (C) with the inductance of counteracting at the coil (L) of the motor (M) of reciprocating type compression unit (L.COMP) itself, switch controlling signal according to microcomputer 40 is closed AC power supplies with TRIAC, so that apply voltage to reciprocating type compression unit (L.COMP).

Describe the operation of the driving-controlling device of reciprocal compressor below in detail.

At first, piston moves by the voltage that applies according to the stroke command that is provided with by the user, therefore, changes stroke and controls refrigeration power.

Simultaneously, when the connection cycle of the TRIAC (Tr1) of circuit unit 10 is prolonged by the switch controlling signal of microcomputer 40, improved the stroke of reciprocating type compression unit (L.COMP).At this moment, the voltage and current that is applied to the motor (M) of reciprocating type compression unit (L.COMP) is detected by voltage detector 30 and current probe 20, and is applied to microcomputer 40.

Then, microcomputer 40 utilizes the electric current and the voltage that are detected by current probe 20 and voltage detector 30 to calculate stroke.

Described stroke by with the stroke command comparison to export corresponding switch controlling signal.

At this, in the present invention, electric capacity (C) is connected in series to motor (M) so that counteracting at the inductance (L) of the coil of motor (M), will describe in detail below.

At first, can derive by following equation (2) for the voltage (V) that is applied to motor (M) and electric capacity (C) two ends: $V=L\frac{\mathrm{di}}{\mathrm{dt}}+\frac{1}{C}\∫\mathrm{idt}+R\·i+\mathrm{\α}\·\stackrel{\→}{S}---\left(2\right)$

At this moment, electric capacity can be set with following equation (3): $C=\frac{1}{{\left(2\mathrm{\πf}\right)}^{2}L}---\left(3\right)$

At this moment, electric capacity (C) and inductance (L) are set to the value that causes resonance in advance.

Therefore, because electric capacity (C) and inductance (L) therefore, can be derived by following equation (4) for the voltage (V) that is applied to motor (M) and electric capacity two ends by resonance and counteracting mutually: $V=R\·i+\mathrm{\α}\·\stackrel{\→}{S}---\left(4\right)$

In equation (4), when inductive drop (

) by capacitance voltage (

) when offsetting, the voltage that is applied (V) have with counterelectromotive force (

) identical size, therefore, produce needed stroke with the low voltage (V) that applies.

In addition, owing to be applied to motor (M) at the voltage of electric capacity (C) as the voltage that applies (V), therefore utilization applies voltage for a short time and has produced big stroke.Therefore, improve overload and resisted electric capacity.

Application on the industry

As to this is described, according to the driving control device of reciprocating compressor, because according in the motor The current practice characteristic of the raising of the inductance of coil is cancelled by use electric capacity, therefore, and the voltage that applies Load for inductance is reduced. So, can produce needed stroke with the low voltage that applies.

In addition, because the change of electric current is very little to the variable effect of stroke, even therefore the load change has taken place, changes stroke is also little, has therefore obtained load characteristic stably.

Claims (3)

1. the driving-controlling device of a reciprocal compressor, it has: a reciprocating type compression unit is used for changing the stroke of piston motion by the voltage that is applied to motor internal with control refrigeration power according to stroke command; A circuit unit is used to utilize TRIAC switch AC power supplies and it is applied to the motor of reciprocating type compression unit,

Wherein circuit unit comprises a capacitor, is used to offset the inductance of coil of the motor of reciprocating type compression unit itself.

2. device as claimed in claim 1, wherein capacitor is placed between motor and the power supply.

3. device as claimed in claim 1, wherein capacitor is placed between motor and the TRIAC.

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